From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chuck Lever Subject: [PATCH 20/24] NFS: Decode NFSv2 read reply using an xdr_stream Date: Sun, 16 May 2010 22:48:34 -0400 Message-ID: <20100517024834.20258.49846.stgit@localhost.localdomain> References: <20100517023905.20258.86631.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" To: linux-nfs@vger.kernel.org Return-path: Received: from mail-qy0-f171.google.com ([209.85.221.171]:63658 "EHLO mail-qy0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752894Ab0EQCsg (ORCPT ); Sun, 16 May 2010 22:48:36 -0400 Received: by mail-qy0-f171.google.com with SMTP id 1so6350026qyk.5 for ; Sun, 16 May 2010 19:48:35 -0700 (PDT) In-Reply-To: <20100517023905.20258.86631.stgit-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: Signed-off-by: Chuck Lever --- fs/nfs/nfs2xdr.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 49 insertions(+), 0 deletions(-) diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c index 164c06d..807c1b1 100644 --- a/fs/nfs/nfs2xdr.c +++ b/fs/nfs/nfs2xdr.c @@ -1032,6 +1032,55 @@ static int nfs2_xdr_dec_readlinkres(struct rpc_rqst *req, __be32 *p, } /* + * 2.2.7. readres + * + * union readres switch (stat status) { + * case NFS_OK: + * fattr attributes; + * nfsdata data; + * default: + * void; + * }; + */ +static int nfs2_xdr_dec_readres(struct rpc_rqst *req, __be32 *p, + struct nfs_readres *result) +{ + struct xdr_stream xdr; + enum nfs_stat status; + u32 recvd, count; + size_t hdrlen; + + xdr_init_decode(&xdr, &req->rq_rcv_buf, p); + if (decode_stat(&xdr, &status) != 0) + return -EIO; + if (status != NFS_OK) + return nfs_stat_to_errno(status); + if (decode_fattr(&xdr, result->fattr) != 0) + return -EIO; + + /* nfsdata */ + p = xdr_inline_decode(&xdr, 4); + if (unlikely(p == NULL)) { + print_overflow_msg(__func__, &xdr); + return -EIO; + } + count = be32_to_cpup(p); + hdrlen = (u8 *)xdr.p - (u8 *)xdr.iov->iov_base; + recvd = xdr.buf->len - hdrlen; + if (count > recvd) { + dprintk("NFS: server cheating in read result: " + "count %u > recvd %u\n", count, recvd); + count = recvd; + } + xdr_read_pages(&xdr, count); + + /* NFSv2 doesn't pass EOF flag on the wire. */ + result->eof = 0; + result->count = count; + return count; +} + +/* * Decode WRITE reply */ static int